Mary and Frank Calandra, Sr., parents of JENNMAR’s two common stockholders, Jack Calandra and Frank Calandra, Jr., originated Frank Calandra, Inc. as a proprietorship in 1922. JENNMAR was incorporated in 1965, but from 1922 until 1972 the company was engaged in various businesses related to the coal mining industry.

In 1972, JENNMAR began to change the primary focus of its business to the manufacturing of roof support systems for coal mines. Today, JENNMAR's reach extends around the globe and into the tunneling and civil construction industries as well.

1922

Frank Calandra, Inc. originated as a proprietorship

1972

Began to change the primary focus of our business to the manufacturing of roof support systems

1975

Continued to grow with the introduction of our first specialty bolt, the COMBINATION® Bolt